Patents Assigned to Hitachi Powered Metals Co., Ltd.
  • Patent number: 8029626
    Abstract: A method for producing a soft magnetic powdered core comprises a mixing step for forming a raw powder by adding a thermoplastic resin powder to a soft magnetic powder and mixing them, a compacting step for forming a compact by compacting the raw powder into a predetermined shape, a melting and setting step for the resin in which the resin of the compact is melted by heating to at least the melting point of the thermoplastic resin and the melted resin is set by cooling to a room temperature, and a crystallizing step for the resin in which the set resin is heated to not less than the exothermic onset temperature and not more than the endothermic onset temperature, which are measured by DSC analysis of the thermoplastic resin, and is cooled to a room temperature.
    Type: Grant
    Filed: March 17, 2008
    Date of Patent: October 4, 2011
    Assignees: Hitachi Powered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuo Asaka, Kohei Muramatsu, Tsuyoshi Akao, Hirotake Hamamatsu
  • Patent number: 7649298
    Abstract: A claw teeth type electric rotary machine comprises a stator including an annular core with claws formed from a powder core and an annular coil installed inside the annular core, and a rotor rotatably positioned inside the stator. An inner edge of the annular core is provided with plural claw poles which are protruded at a predetermined interval in a circumferential direction and extended in an axial direction of the annular core so as to alternately meshes with each other. The stator comprises the annular core with claws, the annular coil, and a molded nonmagnetic potting material filled between the annular core with claws and annular coil, so that the annular core with claws and annular coil are integrated with the molded potting non-magnetic material.
    Type: Grant
    Filed: July 24, 2007
    Date of Patent: January 19, 2010
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Masashi Kitamura, Ryoso Masaki, Katsuyuki Yamazaki, Shoji Ohiwa, Yasuaki Motegi, Kazuo Asaka, Chio Ishihara
  • Patent number: 7605517
    Abstract: A claw pole type rotating electric machine includes first and second claw cores which are disposed on a ring shaped ring yoke portion and a plurality of claw magnetic poles which extend in the axial direction are provided, and stator cores are formed by meshing of the claw magnetic poles with each other, and the stator is formed by holding the ring coils on the outer circumference side of the claw magnetic poles, wherein the first and second claw cores are formed by powder cores, the radial direction thickness of the claw magnetic pole is 2 mm or more, a flat surface is formed perpendicular to the axial direction at the end extending in the axial direction of the claw magnetic pole, a ejection taper in the circumference direction of the claw magnetic pole is formed in the range of 10 degrees or less, and the ratio of the axial direction length of the claw magnetic pole and the axial direction thickness of the ring yoke portion is no more than 5:1.
    Type: Grant
    Filed: September 27, 2006
    Date of Patent: October 20, 2009
    Assignees: Hitachi Industrial Equipment Systems Co., Ltd., Hitachi Powered Metals Co., Ltd., Japan Servo Co., Ltd.
    Inventors: Yuji Enomoto, Motoya Ito, Shoji Ohiwa, Ryozo Masaki, Chio Ishihara
  • Patent number: 7592734
    Abstract: A three-phase permanent magnet brushless motor comprises a stator having three-phase windings, and a rotor having a permanent magnet with a plurality of poles for serving as a field magnet. The stator comprises a stator core which includes a powder core that is compacted at a high density in at least teeth thereof. A combination of the number of magnetic poles of the rotor with the number of slots of the stator satisfies a condition that a least common multiple of the number of slots and the number of magnetic poles is 60 or more in a region in which the number of magnetic poles is 16 or less, and the number of slots is 12 or less. The powder core is made by compacting magnetic powders to have a green density of 7.5 g/cm3 or higher.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: September 22, 2009
    Assignees: Hitachi Industrial Equipment System Co., Ltd., Japan Servo Co., Ltd., Hitachi Powered Metals Co., Ltd.
    Inventors: Yuji Enomoto, Akeshi Takahashi, Motoya Ito, Ryoso Masaki, Katsuyuki Yamazaki, Masahide Yamazaki, Masashi Kitamura, Chio Ishihara, Kazuo Asaka, Shoji Ohiwa, Yasuaki Motegi
  • Publication number: 20080230737
    Abstract: A method for producing a soft magnetic powdered core comprises a mixing step for forming a raw powder by adding a thermoplastic resin powder to a soft magnetic powder and mixing them, a compacting step for forming a compact by compacting the raw powder into a predetermined shape, a melting and setting step for the resin in which the resin of the compact is melted by heating to at least the melting point of the thermoplastic resin and the melted resin is set by cooling to a room temperature, and a crystallizing step for the resin in which the set resin is heated to not less than the exothermic onset temperature and not more than the endothermic onset temperature, which are measured by DSC analysis of the thermoplastic resin, and is cooled to a room temperature.
    Type: Application
    Filed: March 17, 2008
    Publication date: September 25, 2008
    Applicants: HITACHI POWERED METALS CO., LTD., DENSO CORPORATION
    Inventors: Chio Ishihara, Kazuo Asaka, Kohei Muramatsu, Tsuyoshi Akao, Hirotake Hamamatsu
  • Patent number: 7378053
    Abstract: The invention proposes a copper-based material with low thermal expansion and high thermal conductivity having good machinability and adaptability to nickel plating and also proposes a method for producing the same. The copper-based material is prepared through the steps of: adding 5 to 60% of iron-based alloy power having a certain value in thermal expansion coefficient into a matrix powder of pure copper phase powder and/or a precipitation hardening copper alloy powder; mixing the powders together; compacting the obtained powder mixture into a green compact and sintering it at temperatures of 400 to 600° C.
    Type: Grant
    Filed: April 27, 2004
    Date of Patent: May 27, 2008
    Assignee: Hitachi Powered Metals Co., Ltd.
    Inventor: Zenzo Ishijima
  • Publication number: 20070196231
    Abstract: A soft magnetic sintered member having uniform dispersion of alloy elements and a production method for the same at low cost are provided. The soft magnetic sintered member consists of, all in mass %, 2.9 to 7% of Cr; 1.5 to 6.88% of Si; and the balance of Fe and inevitable impurities. The production method for a soft magnetic sintered member includes: preparing an Fe alloy powder consisting of 3 to 7 mass % of Cr, 1.5 to 3.5 mass % of Si, and the balance of Fe and inevitable impurities; or a mixed powder in which the Fe alloy powder is mixed with an Si powder having an average particle size of 1 to 45 ?m. The production method further includes: compacting the Fe alloy powder or the mixed powder into a green compact having a predetermined shape; and sintering the green compact.
    Type: Application
    Filed: March 29, 2005
    Publication date: August 23, 2007
    Applicant: HITACHI POWERED METALS CO., LTD.
    Inventors: Chio Ishihara, Kazuo Asaka
  • Patent number: 7014367
    Abstract: An oil-impregnated sintered sliding bearing formed of a porous iron-based sintered alloy with quenched structure and receiving a high surface pressure capable of reducing the number of finishing steps by cutting and grinding and providing a bearing performance equivalent to or higher than that of conventional bearings, wherein a plurality of ridge-and-groove lines having a height difference of 2 to 12.5 ?m and extending in circumferential direction are axially arranged in parallel with each other by boring the bearing surface thereof to form a wavy surface in axial direction, and the portion thereof deeper by 10 to 60 ?m from the outer layer of the bearing surface is formed dense to seal surface pores so as to reduce the pores opening to the outer surface to 1 to 10 percent by area, whereby the bearing can be used at a surface pressure of 6 kgf/mm2 (58.5 MPa) or higher and a sliding speed of 2 to 5 cm/s.
    Type: Grant
    Filed: January 20, 2003
    Date of Patent: March 21, 2006
    Assignees: Hitachi Powered Metals Co., Ltd., Hitachi Construction Machinery Co., Ltd.
    Inventors: Motohiro Miyasaka, Kazuo Maruyama, Michiharu Mogami, Junichi Kobayashi, Hideki Akita, Osamu Gokita
  • Publication number: 20050242460
    Abstract: The present invention provides a production method for a powdered core, including steps of preparing a mixture including a soft magnetic powder and a resin powder to obtain a mixture, compacting the mixture into a predetermined shape to obtain a green compact and heating the green compact, and wherein the resin powder has a median size of not more than 50 ?m, and the resin powder amount is 0.01 to 5 vol %. The method reduces production cost, and decreases eddy-current loss We and hysteresis loss Wh, whereby a powdered core in which a durability is improved and the technical advantages are expanded can be provided.
    Type: Application
    Filed: September 30, 2003
    Publication date: November 3, 2005
    Applicants: Hitachi Powered Metals Co., Ltd., Denso Corporation
    Inventors: Chio Ishihara, Kazuko Asaka, Kei Ishii, Tamio Takada, Tsuyoshi Akao, Isao Makino
  • Patent number: 6139975
    Abstract: In a method of manufacturing a sheet member comprising: obtaining a sintered compact by sintering a sheet-like compact having a reduced-thickness portion and an enlarged-thickness portion; and then repressing the sintered compact into a sheet member, a difference in density between the reduced-thickness portion and the enlarged-thickness portion of the sintered compact after repressing is adjusted to be in a range of .+-.1.5%. By doing so, the accuracy of flatness is enhanced and the amount of distortion, which would otherwise remain in the sheet member, is reduced because the sheet member is formed by sintering the sheet-like compact. In addition, the deformation caused by heating is greatly restricted. Accordingly, the prospect of the sheet member of the present invention is bright as a heat dissipating plate.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: October 31, 2000
    Assignee: Hitachi Powered Metals Co., Ltd.
    Inventors: Osamu Mawatari, Junichi Ichikawa, Zenzo Ishijima, Hideo Shikata
  • Patent number: 5967110
    Abstract: There is disclosed a method for manufacturing an Fe-based sintered alloy which is superb in machinability. This process comprises the steps of coating a paste-like coating agent including a compound of boron to a surface of a compact of Fe-based or Fe, Cu-based sintered alloy powder including carbon or a pre-sintered compact obtained by heating the compact at a diffusion temperature or less of carbon, and sintering a resultant compact or a pre-sintered compact at a diffusion temperature or more of carbon. An Fe-based sintered alloy manufactured through this process and a bearing cap made of such an Fe-based sintered alloy are also disclosed. In the invention, a film including a compound of boron and pyrolytic resin can be used instead of the paste-like coating agent.
    Type: Grant
    Filed: April 23, 1998
    Date of Patent: October 19, 1999
    Assignee: Hitachi Powered Metals Co., Ltd.
    Inventors: Tadayuki Tsutsui, Bo Hu, Kei Ishii, Hideo Shikata, Jun Sakai
  • Patent number: 5895119
    Abstract: A bearing comprising different materials having oil-filled pores in them has a relief space in the middle section which is not provided by machining. The materials are different, have different characteristics, and bear different portions of load the bearing supports, resulting in longer bearing life and reduced noise. Materials 1 and 2 are separately formed and sintered in such a way that material 1 has smaller pores in it and can support higher load, material 2 has larger pores in it and can support lower load, and an end portion of each material is stepped so that material 1 can be partially inserted into material 2 and a relief space is provided on the inner periphery of material 1. The materials 1 and 2 are then joined together into one piece, and the one piece is placed in a sizing die and pressed. The sized one piece is a strong one-piece bearing having an accurate inside diameter and good concentric alignment.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: April 20, 1999
    Assignees: Hitachi Powered Metals Co., Ltd., Matsushita Electric Industrial Co., Ltd.
    Inventors: Motohiro Miyasaka, Makoto Kondo, Shigeru Otsuka